Respiratory Pathogens 1

Question 1

what is he degree of pathogenicity of a disease determined y

Answer 1

proteins it expresses and how effectively it cn integrate enviro info

Question 2

what are some virulence mechanisms

Answer 2

bac adhesion
bac invasion
bac evsion host defnece
bac toxins

Question 3

what is the cycle of bac infectivity

Answer 3

entry 
attachment
multiplication
evasion of host defences
cause damage
release
spread

Question 4

what are the components of bc adhesion

Answer 4

structure ligand
surface mol
receptors

Question 5

what are some imp structure ligands

Answer 5

capsule (s progenies)
fimbriae (B pertusis)
cell wall (s aureus)
fibrils (s snguinis)

Question 6

what are some imp surface mols receptors

Answer 6

keratinocytes 
laryngeal epi cells 
epi cells
platelets
salivary proteins

Question 7

what can bac adhesion be

Answer 7

superificl/sytemic (metastasis)
extra or intracellular
access via general contact or injection

Question 8

what are some examples of invasion

Answer 8

organism erodes tooth
organsim persisks in epi
org injected via arthropod

Question 9

what are some common bac assc with caries and perio disease

Answer 9

caries - s mutans

peio - p gingivalis

Question 10

lames disease from

Answer 10

borrelia burghdorferi

Question 11

what does penetration of epithelium lead to

Answer 11

blood vessel end = blood circ
to phagocytic cells = both
lymphatic tissue end = accumulates in lymph nodes

Question 12

what are some ways a bacteria can evade host defences

Answer 12

immunity at mucosal surfaces 
destroy immune cells 
interfere with inflam response
evade innate immunity 
overcome acquires immune response

Question 13

how can a bacteria have immunity at mucosal surfaces

Answer 13

production of glycosidases and Sialidases
(s cocci and veillonlela)
proteases
binding proteins

Question 14

why is glycosylation of bac imp

Answer 14

imp for structure and function and resit to proteases

Question 15

why is silica acid on IgA imp

Answer 15

imp for immunoglobulin function

Question 16

what do proteases do

Answer 16

cleave hinge region of IgA normally protected by glycosylation
(s sanguines)

Question 17

what do the binding proteins assc with mucosal surface immunity do

Answer 17

M family proteins
bind Fc region of iG
(s pyogeens and s aureus)

Question 18

how does a bac interfere with cytokines

Answer 18

bac induce septic an ixic shock
TNF a, interferon and interleukins
myeloid, lymphoid and vasc respond to infection

Question 19

what are cytokines

Answer 19

group of regulatory proteins key to immune response

Question 20

what are endotoxins

Answer 20

gm -ve cell wall

LPS outer mem complex

Question 21

what are LPS components

Answer 21

toxicity - lipid A

immunogenicity - polysacc

Question 22

what does endotoxins induce

Answer 22

variety of inappropriate inflam responses that impair hosts response to pathogen

Question 23

what does he outer mem of gm -ve bac consist of

Answer 23

assymetirc mem 
LPS
peptidoglycan
lipoproteins
bind to receps on macrophages, b cells and other cells = cytokines

Question 24

what is SIRS

Answer 24

systemic Inflammatory Response Syndrome

Question 25

what are the ways of inflam cytokines being released

Answer 25

macrophages activated by LPS/endotixn or peptidoglycan or t cells activated by exotoxins

Question 26

how is complement evaded

Answer 26

capsules - prevent activation of C3 and C3B - mask bound C3b

Question 27

how is there evasion of phagocytic killing

Answer 27

PVL - s aureus intracellular survival -- M TB type 3 secretion systems

Question 28

how is acquired immune repossess overcome

Answer 28

phase variation and antigenic variation

Question 29

what is phase variation

Answer 29

switch between on and off forms of a gene flagellin gene of salmonella opacity genes of neisseria

Question 30

what is antigenic variation

Answer 30

allows bac to change sequence of a gene | pilin genes of neisseira

Question 31

what are the early symptoms of diphtheria

Answer 31

sore throat, low fever, swollen neck glands

Question 32

what are the late stages of diphtheria

Answer 32

airway obstruction breathing difficulty shock

Question 33

what are outbreaks of diphtheria assc with

Answer 33

unsanitary conditions immunity gaps vaccination fail

Question 34

what is the product of diphtheria

Answer 34

toxin = acute inflammation and formation of pseudomembrane - dead tissue - fibrin - polymorphs

Question 35

what causes diphtheria

Answer 35

corynebacterium diphtheria - gm +ve bacilli - aerobic non motile - toxin prod

Question 36

how is diphtheria transmitted

Answer 36

direct contact droplets/skin, or indirect via contaminated object

Question 37

explain some characteristics of corynebacterium diphtheria

Answer 37

``` sol 3 domain P's endocytosed proteolytic cleavage catalytic domain translocate domain ```

Question 38

what is the treatment of diphtheria

Answer 38

inoculation with antitoxin | penicillin or erythromycin to slim bac

Question 39

how is diphtheria prevented

Answer 39

active immunisation diphtheria formal toxin booster and multiple vaccine

Question 40

what is whooping cough

Answer 40

highly contagious | life threatening

Question 41

what causes whooping cough

Answer 41

bordetella pertussis | gm -ve cocci

Question 42

what are the symptoms of whooping cough

Answer 42

``` severe cough low/no fever at start choking nocturnal coughing short breath vomit ```

Question 43

how does bordetella pertussis enter

Answer 43

via resp tract attach to ciliated epi mediated by filamentous hem agglutinin pert actin

Question 44

what is pertactin

Answer 44

outer mem protein | promotes attach to tracheal epi cells

Question 45

what are the toxins assc with bordetetlla pertussis

Answer 45

pertussis toxin adenylate cyclase tracheal cytotoxin

Question 46

what does tracheal cytotoxin do

Answer 46

kills ciliated cells and stimulates their extrusion from the mucosa

Question 47

what is pathogenesis

Answer 47

growth on ciliate epi and toxin prod - paralyse cilia tracheal cytotoxin - stim inflam resp - kill leucocytes

Question 48

what does pertussis toxin do

Answer 48

disrupts cell function increases mucus secretion incapacitates phagocytes

Question 49

what is the diagnosis and treatment of whooping cough

Answer 49

``` cough plate swab pharyngeal walls erythromycin remove mucus Ab therapy for secondary infections ```

Question 50

how is whooping cough vaccinate

Answer 50

part of multiple vaccine kill b pertussis 3 antigenic types